protected boolean handleLocalTunnel(
      TrackerWebPageRequest request, TrackerWebPageResponse response) throws IOException {
    start();

    if (SRP_VERIFIER == null || !active) {

      throw (new IOException("Secure pairing is not enabled"));
    }

    boolean good_request = false;

    try {
      // remove /pairing/tunnel/

      String url = request.getURL().substring(16);

      int q_pos = url.indexOf('?');

      Map<String, String> args = new HashMap<String, String>();

      if (q_pos != -1) {

        String args_str = url.substring(q_pos + 1);

        String[] bits = args_str.split("&");

        for (String arg : bits) {

          String[] x = arg.split("=");

          if (x.length == 2) {

            args.put(x[0].toLowerCase(), x[1]);
          }
        }

        url = url.substring(0, q_pos);
      }

      if (url.startsWith("create")) {

        String ac = args.get("ac");
        String sid = args.get("sid");

        if (ac == null || sid == null) {

          throw (new IOException("Access code or service id missing"));
        }

        if (!ac.equals(manager.peekAccessCode())) {

          throw (new IOException("Invalid access code"));
        }

        PairedServiceImpl ps = manager.getService(sid);

        if (ps == null) {

          good_request = true;

          throw (new IOException("Service '" + sid + "' not registered"));
        }

        PairedServiceRequestHandler handler = ps.getHandler();

        if (handler == null) {

          good_request = true;

          throw (new IOException("Service '" + sid + "' has no handler registered"));
        }

        JSONObject json = new JSONObject();

        JSONObject result = new JSONObject();

        json.put("result", result);

        byte[] ss = new byte[] {SRP_SALT[0], SRP_SALT[1], SRP_SALT[2], SRP_SALT[3]};

        long tunnel_id = RandomUtils.nextSecureAbsoluteLong();

        String tunnel_name = Base32.encode(ss) + "_" + tunnel_id;

        synchronized (local_server_map) {
          long diff = SystemTime.getMonotonousTime() - last_local_server_create_time;

          if (diff < 5000) {

            try {
              long sleep = 5000 - diff;

              System.out.println("Sleeping for " + sleep + " before starting srp");

              Thread.sleep(sleep);

            } catch (Throwable e) {
            }
          }

          SRP6Server server = new SRP6Server();

          server.init(N_3072, G_3072, SRP_VERIFIER, new SHA256Digest(), RandomUtils.SECURE_RANDOM);

          BigInteger B = server.generateServerCredentials();

          local_server_map.put(tunnel_name, new Object[] {server, handler, null, null});

          last_local_server_create_time = SystemTime.getMonotonousTime();

          total_local_servers++;

          result.put("srp_salt", Base32.encode(SRP_SALT));

          result.put("srp_b", Base32.encode(B.toByteArray()));

          Map<String, String> headers = request.getHeaders();

          String host = headers.get("host");

          // remove port number

          int pos = host.lastIndexOf("]");

          if (pos != -1) {

            // ipv6 literal

            host = host.substring(0, pos + 1);

          } else {

            pos = host.indexOf(':');

            if (pos != -1) {

              host = host.substring(0, pos);
            }
          }

          String abs_url = request.getAbsoluteURL().toString();

          // unfortunately there is some nasty code that uses a configured tracker
          // address as the default host

          abs_url = UrlUtils.setHost(new URL(abs_url), host).toExternalForm();

          pos = abs_url.indexOf("/create");

          String tunnel_url = abs_url.substring(0, pos) + "/id/" + tunnel_name;

          result.put("url", tunnel_url);
        }

        response.getOutputStream().write(JSONUtils.encodeToJSON(json).getBytes("UTF-8"));

        response.setContentType("application/json; charset=UTF-8");

        response.setGZIP(true);

        good_request = true;

        return (true);

      } else if (url.startsWith("id/")) {

        String tunnel_name = url.substring(3);

        Object[] entry;

        synchronized (local_server_map) {
          entry = local_server_map.get(tunnel_name);

          if (entry == null) {

            good_request = true;

            throw (new IOException("Unknown tunnel id"));
          }
        }

        String srp_a = args.get("srp_a");
        String enc_data = args.get("enc_data");
        String enc_iv = args.get("enc_iv");

        if (srp_a != null && enc_data != null && enc_iv != null) {

          try {
            synchronized (local_server_map) {
              long diff = SystemTime.getMonotonousTime() - last_local_server_agree_time;

              if (diff < 5000) {

                try {
                  long sleep = 5000 - diff;

                  System.out.println("Sleeping for " + sleep + " before completing srp");

                  Thread.sleep(sleep);

                } catch (Throwable e) {
                }
              }
            }

            JSONObject json = new JSONObject();

            JSONObject result = new JSONObject();

            json.put("result", result);

            SRP6Server server = (SRP6Server) entry[0];

            BigInteger A = new BigInteger(Base32.decode(srp_a));

            BigInteger serverS = server.calculateSecret(A);

            byte[] shared_secret = serverS.toByteArray();

            Cipher decipher = Cipher.getInstance("AES/CBC/PKCS5Padding");

            byte[] key = new byte[16];

            System.arraycopy(shared_secret, 0, key, 0, 16);

            SecretKeySpec secret = new SecretKeySpec(key, "AES");

            decipher.init(Cipher.DECRYPT_MODE, secret, new IvParameterSpec(Base32.decode(enc_iv)));

            byte[] dec = decipher.doFinal(Base32.decode(enc_data));

            JSONObject dec_json = (JSONObject) JSONUtils.decodeJSON(new String(dec, "UTF-8"));

            String tunnel_url = (String) dec_json.get("url");

            if (!tunnel_url.contains(tunnel_name)) {

              throw (new IOException("Invalid tunnel url"));
            }

            String endpoint_url = (String) dec_json.get("endpoint");

            entry[2] = secret;
            entry[3] = endpoint_url;

            result.put("state", "activated");

            response.getOutputStream().write(JSONUtils.encodeToJSON(json).getBytes("UTF-8"));

            response.setContentType("application/json; charset=UTF-8");

            response.setGZIP(true);

            good_request = true;

            return (true);

          } catch (Throwable e) {

            throw (new IOException(Debug.getNestedExceptionMessage(e)));

          } finally {

            last_local_server_agree_time = SystemTime.getMonotonousTime();
          }
        } else if (args.containsKey("close")) {

          synchronized (local_server_map) {
            local_server_map.remove(tunnel_name);
          }

          good_request = true;

          return (true);

        } else {

          PairedServiceRequestHandler request_handler = (PairedServiceRequestHandler) entry[1];

          SecretKeySpec secret = (SecretKeySpec) entry[2];

          String endpoint_url = (String) entry[3];

          if (secret == null) {

            throw (new IOException("auth not completed"));
          }

          byte[] request_data = FileUtil.readInputStreamAsByteArray(request.getInputStream());

          try {
            byte[] decrypted;

            {
              byte[] IV = new byte[16];

              System.arraycopy(request_data, 0, IV, 0, IV.length);

              Cipher decipher = Cipher.getInstance("AES/CBC/PKCS5Padding");

              decipher.init(Cipher.DECRYPT_MODE, secret, new IvParameterSpec(IV));

              decrypted = decipher.doFinal(request_data, 16, request_data.length - 16);
            }

            byte[] reply_bytes =
                request_handler.handleRequest(
                    request.getClientAddress2().getAddress(), endpoint_url, decrypted);

            {
              Cipher encipher = Cipher.getInstance("AES/CBC/PKCS5Padding");

              encipher.init(Cipher.ENCRYPT_MODE, secret);

              AlgorithmParameters params = encipher.getParameters();

              byte[] IV = params.getParameterSpec(IvParameterSpec.class).getIV();

              byte[] enc = encipher.doFinal(reply_bytes);

              byte[] rep_bytes = new byte[IV.length + enc.length];

              System.arraycopy(IV, 0, rep_bytes, 0, IV.length);
              System.arraycopy(enc, 0, rep_bytes, IV.length, enc.length);

              response.getOutputStream().write(rep_bytes);

              response.setContentType("application/octet-stream");

              good_request = true;

              return (true);
            }
          } catch (Throwable e) {

            throw (new IOException(Debug.getNestedExceptionMessage(e)));
          }
        }
      }

      throw (new IOException("Unknown tunnel operation"));

    } finally {

      if (!good_request) {

        manager.recordRequest(
            "SRP", request.getClientAddress2().getAddress().getHostAddress(), false);
      }
    }
  }
  protected boolean generate(TrackerWebPageRequest request, TrackerWebPageResponse response)
      throws IOException {
    InetSocketAddress local_address = request.getLocalAddress();

    if (local_address == null) {

      return (false);
    }

    String host = local_address.getAddress().getHostAddress();

    String url = request.getURL();

    if (TRACE) {
      System.out.println("url: " + url);
    }

    if (!url.startsWith("/TiVoConnect?")) {

      return (false);
    }

    int pos = url.indexOf('?');

    if (pos == -1) {

      return (false);
    }

    String[] bits = url.substring(pos + 1).split("&");

    Map<String, String> args = new HashMap<String, String>();

    for (String bit : bits) {

      String[] x = bit.split("=");

      args.put(x[0], URLDecoder.decode(x[1], "UTF-8"));
    }

    if (TRACE) {
      System.out.println("args: " + args);
    }

    // root folder /TiVoConnect?Command=QueryContainer&Container=%2F

    String command = args.get("Command");

    if (command == null) {

      return (false);
    }

    String reply = null;

    if (command.equals("QueryContainer")) {

      String container = args.get("Container");

      if (container == null) {

        return (false);
      }

      if (container.equals("/")) {

        reply =
            "<?xml version=\"1.0\" encoding=\"UTF-8\" ?>"
                + NL
                + "<TiVoContainer>"
                + NL
                + "    <Details>"
                + NL
                + "        <Title>"
                + server_name
                + "</Title>"
                + NL
                + "        <ContentType>x-container/tivo-server</ContentType>"
                + NL
                + "        <SourceFormat>x-container/folder</SourceFormat>"
                + NL
                + "        <TotalItems>1</TotalItems>"
                + NL
                + "    </Details>"
                + NL
                + "    <Item>"
                + NL
                + "        <Details>"
                + NL
                + "            <Title>"
                + server_name
                + "</Title>"
                + NL
                + "            <ContentType>x-container/tivo-videos</ContentType>"
                + NL
                + "            <SourceFormat>x-container/folder</SourceFormat>"
                + NL
                + "        </Details>"
                + NL
                + "        <Links>"
                + NL
                + "            <Content>"
                + NL
                + "                <Url>/TiVoConnect?Command=QueryContainer&amp;Container="
                + urlencode("/Content")
                + "</Url>"
                + NL
                + "                <ContentType>x-container/tivo-videos</ContentType>"
                + NL
                + "            </Content>"
                + NL
                + "        </Links>"
                + NL
                + "    </Item>"
                + NL
                + "    <ItemStart>0</ItemStart>"
                + NL
                + "    <ItemCount>1</ItemCount>"
                + NL
                + "</TiVoContainer>";

      } else if (container.startsWith("/Content")) {

        boolean show_categories = getShowCategories();

        String recurse = args.get("Recurse");

        if (recurse != null && recurse.equals("Yes")) {

          show_categories = false;
        }

        TranscodeFileImpl[] tfs = getFiles();

        String category_or_tag = null;

        Map<String, ContainerInfo> categories_or_tags = null;

        if (show_categories) {

          if (container.startsWith("/Content/")) {

            category_or_tag = container.substring(container.lastIndexOf('/') + 1);

          } else {

            categories_or_tags = new HashMap<String, ContainerInfo>();
          }
        }

        // build list of applicable items

        List<ItemInfo> items = new ArrayList<ItemInfo>(tfs.length);

        for (TranscodeFileImpl file : tfs) {

          if (!file.isComplete()) {

            // see if we can set up a stream xcode for this but only if we
            // know the duration and the transcode is in progress (done in setup)

            if (!setupStreamXCode(file)) {

              continue;
            }
          }

          if (category_or_tag != null) {

            boolean hit = false;

            String[] cats = file.getCategories();
            String[] tags = file.getTags(true);

            for (String[] strs : new String[][] {cats, tags}) {

              for (String c : strs) {

                if (c.equals(category_or_tag)) {

                  hit = true;
                }
              }
            }

            if (!hit) {

              continue;
            }
          }

          FileInfo info = new FileInfo(file, host);

          if (info.isOK()) {

            boolean skip = false;

            if (categories_or_tags != null) {

              String[] cats = file.getCategories();
              String[] tags = file.getTags(true);

              if (cats.length > 0 || tags.length > 0) {

                skip = true;

                for (String[] strs : new String[][] {cats, tags}) {

                  for (String s : strs) {

                    ContainerInfo cont = categories_or_tags.get(s);

                    if (cont == null) {

                      items.add(cont = new ContainerInfo(s));

                      categories_or_tags.put(s, cont);
                    }

                    cont.addChild();
                  }
                }
              }
            }

            if (!skip) {

              items.add(info);
            }
          }
        }

        // sort

        String sort_order = args.get("SortOrder");

        if (sort_order != null) {

          String[] keys = Constants.PAT_SPLIT_COMMA.split(sort_order);

          final List<Comparator<ItemInfo>> comparators = new ArrayList<Comparator<ItemInfo>>();
          final List<Boolean> reverses = new ArrayList<Boolean>();

          for (String key : keys) {

            boolean reverse = false;

            if (key.startsWith("!")) {

              reverse = true;

              key = key.substring(1);
            }

            Comparator<ItemInfo> comp = sort_comparators.get(key);

            if (comp != null) {

              comparators.add(comp);
              reverses.add(reverse);
            }
          }

          if (comparators.size() > 0) {

            Collections.sort(
                items,
                new Comparator<ItemInfo>() {
                  public int compare(ItemInfo i1, ItemInfo i2) {
                    for (int i = 0; i < comparators.size(); i++) {

                      Comparator<ItemInfo> comp = comparators.get(i);

                      int res = comp.compare(i1, i2);

                      if (res != 0) {

                        if (reverses.get(i)) {

                          if (res < 0) {

                            res = 1;

                          } else {

                            res = -1;
                          }
                        }

                        return (res);
                      }
                    }

                    return (0);
                  }
                });
          }
        }

        // select items to return

        String item_count = args.get("ItemCount");
        String anchor_offset = args.get("AnchorOffset");
        String anchor = args.get("AnchorItem");

        int num_items;

        if (item_count == null) {

          num_items = items.size();

        } else {

          // can be negative if X items from end

          num_items = Integer.parseInt(item_count);
        }

        int
            anchor_index; // either one before or one after item to be returned depending on count
                          // +ve/-ve

        if (num_items < 0) {

          anchor_index = items.size();

        } else {

          anchor_index = -1;
        }

        if (anchor != null) {

          for (int i = 0; i < items.size(); i++) {

            ItemInfo info = items.get(i);

            if (anchor.equals(info.getLinkURL())) {

              anchor_index = i;
            }
          }
        }

        if (anchor_offset != null) {

          anchor_index += Integer.parseInt(anchor_offset);

          if (anchor_index < -1) {

            anchor_index = -1;

          } else if (anchor_index > items.size()) {

            anchor_index = items.size();
          }
        }

        int start_index;
        int end_index;

        if (num_items > 0) {

          start_index = anchor_index + 1;

          end_index = anchor_index + num_items;

        } else {

          start_index = anchor_index + num_items;

          end_index = anchor_index - 1;
        }

        if (start_index < 0) {

          start_index = 0;
        }

        if (end_index >= items.size()) {

          end_index = items.size() - 1;
        }

        int num_to_return = end_index - start_index + 1;

        if (num_to_return < 0) {

          num_to_return = 0;
        }

        String machine = getMachineName();

        if (machine == null) {

          // default until we find out what it is - can't see any way to get it apart from wait for
          // broadcast

          machine = "TivoHDDVR";
        }

        String header =
            "<?xml version=\"1.0\" encoding=\"UTF-8\" ?>"
                + NL
                + "<TiVoContainer>"
                + NL
                + "    <Tivos>"
                + NL
                + "      <Tivo>"
                + machine
                + "</Tivo>"
                + NL
                + "    </Tivos>"
                + NL
                + "    <ItemStart>"
                + start_index
                + "</ItemStart>"
                + NL
                + "    <ItemCount>"
                + num_to_return
                + "</ItemCount>"
                + NL
                + "    <Details>"
                + NL
                + "        <Title>"
                + escape(container)
                + "</Title>"
                + NL
                + "        <ContentType>x-container/tivo-videos</ContentType>"
                + NL
                + "        <SourceFormat>x-container/folder</SourceFormat>"
                + NL
                + "        <TotalItems>"
                + items.size()
                + "</TotalItems>"
                + NL
                + "    </Details>"
                + NL;

        reply = header;

        for (int i = start_index; i <= end_index; i++) {

          ItemInfo item = items.get(i);

          if (item instanceof FileInfo) {

            FileInfo file = (FileInfo) item;

            long file_size = file.getTargetSize();

            String title = escape(file.getName());
            String desc = title;

            int MAX_TITLE_LENGTH = 30;

            if (title.length() > MAX_TITLE_LENGTH) {

              // TiVo has problems displaying a truncated title if it has
              // no spaces in it

              String temp = "";

              for (int j = 0; j < title.length(); j++) {

                char c = title.charAt(j);

                if (Character.isLetterOrDigit(c)) {

                  temp += c;
                } else {

                  temp += ' ';
                }
              }

              int space_pos = temp.indexOf(' ');

              if (space_pos == -1 || space_pos > MAX_TITLE_LENGTH) {

                temp = temp.substring(0, 30) + "...";
              }

              title = temp;
            }

            reply +=
                "    <Item>"
                    + NL
                    + "        <Details>"
                    + NL
                    + "            <Title>"
                    + title
                    + "</Title>"
                    + NL
                    + "            <ContentType>video/x-tivo-mpeg</ContentType>"
                    + NL
                    + "            <SourceFormat>video/x-ms-wmv</SourceFormat>"
                    + NL;

            if (file_size > 0) {
              reply += "            <SourceSize>" + file_size + "</SourceSize>" + NL;
            } else {
              long est_size = file.getEstimatedTargetSize();

              if (est_size > 0) {
                reply += "            <SourceSize>" + est_size + "</SourceSize>" + NL;
              }
            }

            reply +=
                "            <Duration>"
                    + file.getDurationMillis()
                    + "</Duration>"
                    + NL
                    + "            <Description>"
                    + desc
                    + "</Description>"
                    + NL
                    + "            <SourceChannel>0</SourceChannel>"
                    + NL
                    + "            <SourceStation></SourceStation>"
                    + NL
                    + "            <SeriesId></SeriesId>"
                    + NL
                    + "            <CaptureDate>"
                    + file.getCaptureDate()
                    + "</CaptureDate>"
                    + NL
                    + "        </Details>"
                    + NL
                    + "        <Links>"
                    + NL
                    + "            <Content>"
                    + NL
                    + "                <ContentType>video/x-tivo-mpeg</ContentType>"
                    + NL
                    + "                    <AcceptsParams>No</AcceptsParams>"
                    + NL
                    + "                    <Url>"
                    + file.getLinkURL()
                    + "</Url>"
                    + NL
                    + "                </Content>"
                    + NL
                    + "                <CustomIcon>"
                    + NL
                    + "                    <ContentType>video/*</ContentType>"
                    + NL
                    + "                    <AcceptsParams>No</AcceptsParams>"
                    + NL
                    + "                    <Url>urn:tivo:image:save-until-i-delete-recording</Url>"
                    + NL
                    + "                </CustomIcon>"
                    + NL
                    + "        </Links>"
                    + NL
                    + "    </Item>"
                    + NL;

          } else {

            ContainerInfo cont = (ContainerInfo) item;

            reply +=
                "    <Item>"
                    + NL
                    + "        <Details>"
                    + NL
                    + "            <Title>"
                    + cont.getName()
                    + "</Title>"
                    + NL
                    + "            <ContentType>x-container/tivo-videos</ContentType>"
                    + NL
                    + "            <SourceFormat>x-container/folder</SourceFormat>"
                    + NL
                    + "            <TotalItems>"
                    + cont.getChildCount()
                    + "</TotalItems>"
                    + NL
                    + "        </Details>"
                    + NL
                    + "        <Links>"
                    + NL
                    + "            <Content>"
                    + NL
                    + "                <Url>"
                    + cont.getLinkURL()
                    + "</Url>"
                    + NL
                    + "                <ContentType>x-container/tivo-videos</ContentType>"
                    + NL
                    + "            </Content>"
                    + NL
                    + "        </Links>"
                    + NL
                    + "    </Item>"
                    + NL;
          }
        }

        String footer = "</TiVoContainer>";

        reply += footer;
      }

    } else if (command.equals("QueryFormats")) {

      String source_format = args.get("SourceFormat");

      if (source_format != null && source_format.startsWith("video")) {

        // /TiVoConnect?Command=QueryFormats&SourceFormat=video%2Fx-tivo-mpeg

        reply =
            "<?xml version=\"1.0\" encoding=\"utf-8\"?>"
                + NL
                + "<TiVoFormats><Format>"
                + NL
                + "<ContentType>video/x-tivo-mpeg</ContentType><Description/>"
                + NL
                + "</Format></TiVoFormats>";
      }
    }

    if (reply == null) {

      return (false);
    }

    if (TRACE) {
      System.out.println("->" + reply);
    }

    response.setContentType("text/xml");

    response.getOutputStream().write(reply.getBytes("UTF-8"));

    return (true);
  }